Improvement in pavements



w; w. HUBBELL. Improvement in Pavements. |\|0.-115,475. Patented May 30,1871.

bed andthecobblj ceive the solutionof-g r planof thesame as se 1 UNITED STATES TENT WILLIAM wn nLnR HUBBELL, or PHILADELPHIA, PENNSYLVANIA.

3 [IMPROVEMENT IN PAVEMENTS.

Specificntien forz ning part of- Letters Patent No. 115,475, dated May 30, 1871. V

Be-it known that 1,]WILLIAM WHEELER State of Pennsylvania, have invented a new and useful Improvement in Street Pavement, of which the followingjiis a specification:

The nature of my. invention consists in the manner of constructing a concrete and stone street pavement, with anunder bed of large I stone, cemented and interlocking with an up- 1 per surface of smallercemented stone-for a wearing-surface,'with coal-ashes, cement, and lime, applied andz constructed substantially as hereindescribed; theobject beingto form a pavement which-is not jdestructible by saturation and decomposition, which resists uric acid, wet, heat, and cold, is smooth and easy to the wheels of vehicles, yet gritty and pliant to horses feet, and capable of great wear, and easy renewal of wearing-surface at small expense, and thus superior to any other paveinent forthestreets of cities. o

- Description the Accompanying Drawing,

whichfiepresents the Street; Figure lis the cr section with the graveleljset in it ready to re- Fig.2 is the ground the gravel, showing the interstices between the stones for a foundation or bed; 3 is the cross-section of the HUBBELL, of the] city or Philadelphia and stones.

into the gravel bed in which the stones set, and convert this gravel bed into "cement or concrete. About one bushel of lime slaked in about forty gallons of water should be used I to saturate about six square yards of gravel bed; but I do not confine myself to these exact proportions, as it is manifestthey maybe varied. Before the solution of lime sets in the gravel bed drive the cobbles or stones down well into it. The saturated gravel will then be forced to near the top of the cobble- Then set the gutter-stones 'i on the cobble-stones and concrete; and I now spread over these cobble or broken stones a thin layer of small broken stone, j, which have been prepared or selected for the purpose. These broken stone fshould be durable in their texture, and of about one inch and a half, irregular or cubical in form-what is commonly known as turnpike broken stone. They will necessarily vary some in size and shape, some smaller and some larger. Some of these broken stone will settle down into the crevices or spaces between the cobble-stones or foundation-stones into the concrete, and interlock laterally with them, and, projecting up, will interlock with the larger broken stone, or those over the cobble-stones. When this thin layer of these broken stone is spread it should barely cover the cobble-stones, the object now Enron.

3 stonebed withlthe layer of broken stone and o y concrete. reajdyfto be rolled for asur'facerFig. 1 I ,Axisthe crosssection of the pavement as being to get the interlocking and a firm cement or concrete bed, and connection between this upper and the lower stratum or bed of stone this bedof gravel} a ished for travelin g surface.

In constructing hexpavement I first make eight inches deep,

, abed of grave aboi 1 and distributed earth, b, the upper fa'cee being shape lytofthe lconfiguration of thestreetincu atureandgrade. Into jet cobble-stones d, or broken stones,so :ast leave interstices e be- I "tween them, they. being set about half their depth into the grave w ei1ow. a solution of lime to. settle downbetweenthem, and to allow smaller orlsur'face stone to! interlock with them. g'g aretheycunbstones. When these cobble orbroken stones d are. set or laid in and concrete; and I now make and use a con.

crete of the following materials: Take about four bushels of dry sifted stone-coal ashes and sift or mix it thoroughly with one bushel of Rosendale or hydraulic cement, or similar cement. Now sift this dry ashes and cement over the bed of broken stone, and brush it about so that it shall settledown between V the crevices. Spread it so that it shall cover about six square yards of the bed. Now wa-. ter this with a solution of slaked lime, using about three bushels of lime in forty gallons of water. Now spread over this another slight layer of broken stone, and immediatelyroll I the gravel beda, I have a strong. solution of lime slaked in. water, and pour thissolution onto the stones and between them, with watery I pots. so that it shallbe distributed evenly and shall run and settle down between the stones them all down with heavy rollers, or ram them into the cement bed before it has set, so that they shall. be pressed down solid into it and all interlocking together in a solid mass. Now sift more of this dry mixture of coal-ashes cussions of wheels and horses feet.

and cement over this bed of stone, water it again with the solution of lune, and roll it all down to form a smooth surface, It, so that the upper surfaces of the broken stone will be at or close to the surface of the bed, and form substantially a part thereof to receive the con- A slight coat of fine clean stone gravel or pebble may be spread on it and rolled in, or it may be omitted. 7

By this described method of applying the dry ashes and cement and the solution of lime, they become equally diffused and saturated in. their proper places to solidify, with the least possible labor and expense, which necessary for this purpose of a street pavement.

This concrete bed of stone and this cement will become very solid, and I have found by experiment that such 'a concrete bed will resist the extreme changes of cold and heat, and the action of uric acid and of rains, to which it is exposed, better than any other cheap preparation, and make a superior pavement for the streets of cities.

\Vhcn this pavement is worn into depressions, it is easily repaired and leveled up by loosening the surface with a pick, leveling it up with broken stone, siftingin the ashes and cement, Watering it with the solution of lime, and rollin it down level with the old surface. A new surface dressing can also be put all over the old one in the same manner, at slight expense, and thus readily keep it in good or der for many years, at small expense.

The coal-ashes being a calcined product of he city dwellings makes it conveniently at hand, "and by experiment I find it is better for this purpose than sand or gravel, though they maybe substituted in this process of making up the pavement; but applied in this manner would, I think, be within the scope of my invention. The cement may also be omitted, but it would make the concrete less solid and durable to use a solution of lime alone.

The advantage of making a cement of the lower bed of gravel is that it tends to prevent the stone bed from settling into cavities, and also tends to keep it more solid and drier, though cementing the lower bed may be dispensed with without changing the main principles of my invention.

I do not claim a bituminous composition, formed in layers, applied to and combined with a stone pavement but What I claim as my invention is-- The manner hereinbefore described of building up the concrete and stone pavement by the application of a solutionofllimewithdry coal-ashes or gravel, andRosendale or hydraulic cement, mixed and. sifted into the crevices of the broken stone so that the broken stone shall interlock between the bed and each other with this concrete between them, and form the stone and concrete surface described.

XVM. V. HUBBELL.

Witnesses:

\VALTER HUBBELL, E. A. RAMILLIE. 

